01404 549770 Get a free quote

Underfloor heating not working and need technical support fast? Try our online guidance below. You can also view diagrams of your UFH manifold to select the relevant spare part, most of which can be bought from the Nu-Heat webstore.

If you’re still experiencing problems with a Nu-Heat underfloor heating system, please contact our Technical Support Team via tech.support@nu-heat.co.uk or call 01404 540745 between 8am and 5pm, Monday to Friday.

Underfloor Heating Troubleshooting

Technical Problem: Single flooring zone not heating up

  • Sticky pin valve actuator
    Spray with silicon and gently ease the pin up and down until free. Do not use WD40 or any hydrocarbon based lubricant.
  • Underfloor heating actuator failed
    Check that the actuator head is proud after 3 minutes of calling for heat – if not, replace it. Alternatively, it may not be the actuator – it could be a wiring board or thermostat issue.
  • Faulty underfloor heating thermostat
    Call an electrician – check for live and switched live return. If your system uses wireless, battery-powered thermostats then it’s also a good idea to check the batteries.
  • Thermostat not set up correctly – E1/E2 errors
    neoStat – if you are using a neoStat please view page 9 of the User Guide which explains this error code.
    neoAir – if you are using a neoAir please view page 10 of the User Guide which explains this error code.
  • Air bubble or airlock in UFH loop
    If the underfloor heating is patchy, low flow you will notice the flow gauges trembling download our plumbing manual and follow the procedure for filling and flushing.
  • Wiring issue faulty connection – dry joint
    Call an electrician – check for continuity and loose connections.
  • Flow gauges not been opened correctly on E-manifolds
    a) Lift the locking collar – do not remove completely
    b) Turn the collar anti-clockwise to unscrew the isolation valve. Three turns will fully open the valve – do not exceed this. The isolation valve must be fully open before flow rate adjustment is possible
    c) Push the locking collar back down to lock the isolation valve
    d) Circuit flow rate can be adjusted by twisting the top of the gauge by hand to the desired setting between 0 and 4. Lift the white collar to lock the flow meter setting.

Technical Problem: Multiple or all flooring zones not working

  • Circulation pump failure
    Check for air in the pump and check that the circulation pump is receiving a live signal from the Nu-Heat wiring board.
  • Pump relay on wiring boards
    When a call for heat is present check that the relay makes a clicking sound and it switches.
  • Isolation valves closed on manifold
    The isolation valve is open when it’s in-line with the pipework. If it’s at 90° angle to the pipe it is closed.
  • Blending valve pin valve stuck
    Use silicon spray (not WD40 or any hydrocarbon based lubricant) and gently ease the pin up and down until it is free.
  • Air ingress
    Download our plumbing manual and follow the procedure for filling and flushing.
  • Boiler not firing (no signal)
    Check that the boiler is powered up and that the wiring board is receiving a live signal on (in) and sending this signal back on (out).
  • No power to wiring boards
    Check switches and fused spurs.

Technical Problem: Underfloor heating zone permanently on

  • Faulty actuator (has it been energised/de-energised prior to fitting)
    The pin valve may be stuck in the up position – use silicon spray and gently ease the pin valve up and down.
  • Faulty thermostat
    Does the thermostat have a live supply and a switched live return when it is turned up?

Technical Problem: UFH pump running all the time or won’t turn off

  • Pump relay stuck on the wiring board
    Replace the wiring board having checked the thermostat.
  • Faulty underfloor heating thermostat
    Does the thermostat have a live supply and a switched live return when it is turned up?
  • Faulty underfloor heating actuator
    There are no serviceable parts – replace the actuator.

Identifying your underfloor heating manifold for parts

Choose your manifold from the list below to help select spare parts.

If you need any further help, you can contact our Technical Support Team via techsupport@nu-heat.co.uk or 01404 540745 between 8am and 5pm, Monday to Friday.

Oct 1999 – Apr 2007 – Brass manifolds (OMDxx-C)

OMD Manifold
No. Code Description Buy online
1 OMD1E-C Port extension kit N/A
2 OMFG-C Flow gauges Buy Online
3 G1560-C Pump N/A
4 TGD-C Temperature gauge Buy Online
5 MPP1-A Complete pump module N/A
6 MPPK1-C Pump module assembly N/A
7 OMBV-C Valve set N/A
8 MPBV075-C Blending valve Buy Online
9 DZSW24-C Blending valve insert Buy Online
10 MPPT-C Blending valve head Buy Online
11 OMFV-C Pin section Buy Online
12 ALE075/14-C Nut/olive Buy Online
13 WPEX/xx-C Tube N/A
14 OMDA-C Actuator Buy Online
15 OMDAC-C Actuator collar N/A
16 GC14-C Guide curves Buy Online
17 OMPG-C Pressure gauge N/A
18 OMDS-C Filing/flushing N/A

Apr 2007 – Aug 2009 – Stainless steel manifolds (OMSxx-C)

OMS Manifold
No. Code Description Buy online
1 PM1-A Complete pump module N/A
2 BVM1/F1(R)-C Valve (blue) N/A
3 OMSFG-C Flow gauges Buy Online
4 OMSTG-C Temperature gauge N/A
5 OMSVV-C Air vent N/A
6 OMSPV-C Filing/flushing N/A
7 OMSPG-C Pressure gauge Buy Online
8 OMSB-C Brackets N/A
9 ALE075/14-C Nut/olive Buy Online
10 Pin section N/A
11 UJ14-A PEX couplers Buy Online
12 OMDA-C Actuator Buy Online
13 OMDAC-C Actuator collar N/A
14 BVM1/F1(B)-C Valve (blue) N/A
15 M1/28-C 1″ – 28mm compression N/A
16 BC-C Blanking cap (for ports) Buy Online
17 BV3/4B-C Valve (blue) N/A
17a BV3/4R-C Valve (red) N/A
18 GC14-C Guide curves Buy Online
19 3/4MI22-C 3/4″ – 22mm compression N/A
20 G1560-C Pump N/A
21 PM-C Pump module/blending valve N/A

Aug 2009 – Oct 2010 – Brass plated manifolds (OMExx-C)

OME Manifold
No. Code Description Buy online
1 PM1-A Complete pump module N/A
2 OMEFM-C Flow gauges Buy Online
3 OMETG-C Temperature N/A
4 OMSVV-C Air vent N/A
5 OMEAV-C Air vent N/A
6 OMSPG-C Pressure gauge Buy Online
7 OMEDV-C Filing or flushing N/A
8 ALE075/14-C Nut/olive Buy Online
9 OMEPV-C Pin section N/A
10 OMDA-C Actuator Buy Online
11 OMDAC-C Actuator collar N/A
12a BVM1/F1(B)-C Valve (blue) N/A
12b BVM1/F1(R)-C Valve (red) N/A
13 M1/28-C 1″ – 28mm compression N/A
14a BV3/4B-C Valve (blue) N/A
14b BV3/4R-C Valve (red) N/A
15 UJ14-C Joiner N/A
16 GC14-C Guide curves Buy Online
17 3/4MI22-C 3/4″ – 22mm compression N/A
18 G1560-C Pump N/A
19 PM-C Pump module/blending valve N/A

Oct 2010 – Present – Stainless steel manifolds (OMSxx-C)

OMS Manifold
No. Code Description Buy online
1 PM1-A Complete pump module N/A
2 BVM1/F1(R)-C Valve (blue) N/A
3 OMSFG-C Flow gauges Buy Online
4 OMSTG-C Temperature gauge N/A
5 OMSVV-C Air vent N/A
6 OMSPV-C Filing/flushing N/A
7 OMSPG-C Pressure gauge Buy Online
8 OMSB-C Brackets N/A
9 ALE075/14-C Nut/olive Buy Online
10 Pin section N/A
11 UJ14-A PEX couplers Buy Online
12 OMDA-C Actuator Buy Online
13 OMDAC-C Actuator collar N/A
14 BVM1/F1(B)-C Valve (blue) N/A
15 M1/28-C 1″ – 28mm compression N/A
16 BC-C Blanking cap (for ports) Buy Online
17 BV3/4B-C Valve (blue) N/A
17a BV3/4R-C Valve (red) N/A
18 GC14-C Guide curves Buy Online
19 3/4MI22-C 3/4″ – 22mm compression N/A
20 G1560-C Pump N/A
21 PM-C Pump module/blending valve N/A

If you need any further support, you can contact our Technical Support Team via techsupport@nu-heat.co.uk or 01404 540745 between 8am and 5pm, Monday to Friday.

Start a chat